The invention is generally directed to a flexible container for liquids which stands on its own without the need for a rigid structure and, in particular, to a flexible container for liquids suitable for use in transportation and storage of liquids.
The use of metallic drums for containing and transporting a variety of liquids has posed an environmental threat in various industries in recent years. Over time, the metallic drums have a tendency to wear, rust and leak and require specialized disposal handling procedures once their useful lives are completed. In addition, the energy required to produce the steel and manufacture the drums, including the hazardous primer and paint coatings used, as well as disposal and partial recycling, present a heavy environmental and physical cost to the planet.
In addition to the environmental concerns, drums represent significant dead weight in all transportation modes and additional cargo could be transported if the weight of the drums could be avoided. Generally, when transporting liquids the density of the liquid is such that the volumetric capacity of the trucks or other transporting carriers are not the limiting factor. Rather, it is the weight which limits the amount of cargo that can be transported.
Considerable improvement to the transportation of dry cargo was achieved with the introduction of super sacks or xe2x80x9cbig bagsxe2x80x9d for a multitude of uses and materials. With the new big bags millions of bags ranging from 25 kilogram to 70 kilogram capacity were replaced by the big bags and dry cargo could be moved more efficiently and economically, avoiding labor and speeding up cargo loading and unloading times.
In the past, flexible containers for liquids were generally attached to rigid frames to maintain a desired shape and, more importantly, to maintain the stability of the containers during handling and transportation. Generally, liquids flow within flexible containers and, as the container or the surface on which it rests tilts, the fluid tends to immediately respond to this change in base and flow with gravity to its lowest potential energy state. The effect of this is that generally a flexible container for a liquid will tend to move and shift as it is transported, which can be dangerous and difficult to control.
Accordingly, there is a need for an improved flexible container for liquids which allows safe transport and storage, reduces the tear or packaging weight of the container and improves recycling efficiency.
The invention is generally directed to a flexible container for liquids including an outer shell, an inner liner and an intermediate structure in which the intermediate liner is coupled to the outer shell to maintain a cross-sectional profile and the volume of the inner liner is greater than the enclosed volume of the intermediate structure.
Another object of the invention is to provide an improved process for loading liquids into a flexible container wherein the container is lifted by straps so that the container hangs freely, the container is filled with the liquid, the filling tube is sealed, the sealed tube is placed between the outer shell and stabilizing straps on the outside surface of the outer shell and the flexible container is then rested on a surface, trapping the filling tube between the outside surface and strap so that the container is securely sealed.
Another object of the invention is to provide an improved flexible container for liquids in which a stable structure is obtained which is resistant to tipping or unintended movement of the filled container.
Still another object of the invention is to provide an improved flexible container for liquids in which the container is resistant to puncturing due to use of an inner liner of larger volume than is necessary to fill the volume within the intermediate structure, so that when puncturing elements such as the forks from a forklift truck are pressed against the outer shell of the flexible container, the inner liner resists puncturing.
Yet a further object of the invention is to provide an improved flexible container in which interior or exterior straps are used on the outer shell of the flexible container which are slightly shorter in length than their connection points upon the outer shell so that improved structural rigidity of the filled container is provided.
Yet another object of the invention is to provide an improved flexible container for liquids in which an intermediate structure is connected to the centers of the sides of the outer shell in a fashion which provides a stable, generally rectangular tube which encloses and stabilizes the flexible inner liner.
Yet still another object of the invention is to provide an improved flexible container for liquids in which the outer shell includes horizontal and crossing straps which stabilize the shape of the flexible container, together with an intermediate structure secured to the inside of the outer shell.
Still yet a further object of the invention is to provide an improved flexible container for liquids including a filling tube which is sealed in the filled state between the supporting straps of the outer shell and the outer shell itself by the pressure exerted from within by the liquid in the flexible container.
Still other objects and advantages of the invention will, in part, be obvious and will, in part, be apparent from the specification.
The invention accordingly comprises the features of construction, combination of elements, arrangement of parts, combinations of steps and procedures, all of which will be exemplified in the constructions and processes hereinafter set forth and the scope of the invention will be indicated in the claims.